1. Field of invention
The present invention relates to a refrigerator having a damper device to control taking-in of cooling air and a fan motor to send the cooling air.
2. Related art
Conventionally, a motor type damper device is adopted in a refrigerator (Unexamined Japanese Patent Publication Hei. 6-109354, 9-138052, etc.). A motor type damper device 50 disclosed in Unexamined Japanese Patent Publication Hei. 6-109354, is used for a refrigerator 60 separated into a freezing room 61, a refrigerated room 62 and a vegetable room 63 as shown in FIG. 5. An evaporator 64 is provided on the bottom of the freezing room 61, and a fan motor 65 and an air blower 66 driven by the fan motor 65 are arranged in a rear portion of the evaporator 64. The obtained cooling air is sent to the freezing room 61 or the refrigerated room 62 by the air blower 66. The evaporator 64 absorbs heat of the surroundings when a cooling medium compressed by a compressor 67 is evaporated, and generates cooling air.
A partition plate 68a serving as a partition wall is provided between the evaporator 64 and the refrigerated room 62 and shuts off the cooling air of the evaporator 64 directly flowing to the refrigerated room 62. On the other hand, a cooling air flowing path 69 is formed between the rear portion of the partition plate 68a and the inner wall of the rear portion of the refrigerator 60, and a damper device 50 is arranged in the cooling air flowing path 69.
When a baffle 52 of the damper device 50 is opened, the cooling air flowing path 69, which is a path of the cooling air, is opened in the form of a clank. The damper device 50 is provided in such manner that it is held by a partition wall 68b which is a partition wall forming a portion of the cooling air flowing path 69. In this connection, a damper motor 53 is structured by an AC synchronous motor and conducts the open and close operations of the baffle 52.
Further, a motor type damper device 70 disclosed in Unexamined Japanese Patent Publication Hei. 9-138052, is built in a refrigerator 80 in the form as shown in FIG. 6. Herein, the same members as those shown in FIG. 5 will be shown by the same numerical codes as those in FIG. 5, and the explanation will be omitted.
In this refrigerator 80, a duct 81 whose both ends are opened so as to send the cooling air to the vegetable room 63, is formed as shown in FIG. 6, and a motor type damper device 70 is fitted in a portion leading into the vegetable room 63 in the duct 81. That is, this damper device 70 is fitted in such that a frame 71 of the damper device 70 forms a portion of the duct 81, and the damper device 70 itself serves also as the duct 81. In this connection, the drive source of the motor type damper device 70 is a stepping motor, and opens and closes the baffle 72.
In the refrigerators 60 and 80 using the motor type damper devices 50 and 70, these damper device 50 and 70 are operated by temperature sensors in the refrigerated room 62 and vegetable room 63. Concretely, the refrigerators are controlled by a control circuit 91 as shown in FIG. 7. That is, the fan motor (FM) 65 is connected in parallel to the compressor (CP) 67 to operate the evaporator 64, and both members 65 and 67 are controlled by a thermo-switch 92 for the freezing room 61. On the other hand, in the refrigerated room 62, a bimetal thermo-switch 93 for the damper is provided, and the motor type damper device 50 is connected to it. The bimetal thermo-switch 93 for the damper has an open-terminal 93a to open the baffle 52 of the damper device 50 so as to take in the cooling air when the room temperature is higher than a setting temperature value, and a close-terminal 93b to close the baffle 52 so as to shut off the cooling air when the room temperature is lower than a setting value which is set lower than the above-described setting temperature value.
The motor type damper device 50 has a damper motor 94 structured by an AC synchronous motor or a stepping motor; a close-operation switch 95 which supplies a current to the damper motor 94 until, when the bimetal thermo-switch 93 contacts the closing terminal 93b side, the baffle 52 of the damper device 50 is operated in the closing direction and the baffle is fully closed, and which is opened and stops the current supply when the baffle 52 is closed; and an open-operation switch 96 which is interlocked with the close-operation switch 95 simultaneously when it is opened, and which conducts an on-operation, that is, close operation.
Incidentally, the structure and operations of the motor type damper device 70 are also the same as those of the motor type damper device 50, and therefore, the explanation will be omitted.
The conventional refrigerators 60 and 80 having the motor type damper devices control the motor type damper devices 50 and 70 by the bimetal thermo-switch 93, or the like, in the refrigerated room 62 or vegetable room 63. However, only making the motor type damper devices 50 and 70 on and off, it is difficult to conduct the cooling of the refrigerated room 62 or vegetable room 63 at high speed.
For example, in the case where the fan motor 65 provided on the rear portion of the evaporator 64 is operated, when the baffle 52 of the motor type damper device 50 for the refrigerated room 62 is opened, the temperature of the refrigerated room 62 is quickly lowered and reaches a predetermined value soon. However, in the case where the fan motor 65 is not operated, even if the motor type damper device 50 is opened, the cooling air hardly enters into the refrigerated room 62. Accordingly, in this case, it requires a long period of time to cool down the temperature to a predetermined value.